I tried to update a new Lenovo TS130 with SP1 MS 2008 Server R2.
I got error code 800F0818 and Error 800F081E.
This is a question best asked in the Windows Server forums. Plugging those two error codes into a web search would be a good approach also. The 0x800F0818 suggets that your SP1 installation package is corrupted.
When/where did you download it? I suggest deleting it and re-downloading the current SP1 installer from the Microsoft Download Center.
Lawrence Garvin, M.S., MCITP:EA, MCDBA, MCSA
Product Manager, SolarWinds
Microsoft MVP - Software Distribution (2005-2012)
My MVP Profile: http://mvp.support.microsoft.com/profile/Lawrence.Garvin